Time-delay control unit for demolition operations and the like



Oct. 1, 1969 I Rw. HEINEMANN ETAL 3,470,819

TIME-DELAY CONTROL UNIT FOR DEMOLITION OPERATIONS AND THE LIKE Filed May10, 1968 2 Sheets-Sheet 3.

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INVENTORS ROBERT w HEI'NEMANN EDWARD G. GREENE J ywm- ATTORN EYS.

Oct. 7, 1969 R. w. HEINEMANN ETAL 3,470,819

TIME-DELAY CONTROL UNI-T FOR DEMOLITION OPERATIONS AND THE LIKE FiledMay 10, 1968 2 Sheets-Sheet 2 INVENTOR S. ROBERT W. HEINEMANh EDWARD-G.REENE MAW; m. L M, M w; J W ATTORNEYS.

United States Patent 3,470,819 TIME-DELAY CONTROL UNIT FOR DEMOLITIONOPERATIONS AND THE LIKE Robert W. Heinemann, Dover, and Edward G.Greene, Rockaway, N.J., assignors to the United States of America asrepresented by the Secretary of the Army Filed May 10, 1968, Ser. No.728,233 Int. Cl. F42c 9/02 US. Cl. 10282 9 Claims ABSTRACT OF THEDISCLOSURE A time-delay control unit which can be provided in quantityfor mine inactivation or demolition control. Each unit includes a casingin two complementary parts or halves held together by rivets andprovided with a ventilated cylindrical chamber for a timer element orplug of elastomer material which is expanded or enlarged to fill thechamber by immersion in a volatile solvent prior to use. Aspring-pressed movable piston or plunger bears against one end of thetimer plug and is movable, as the volatile solvent evaporates andshrinks the plug, to withdraw a trigger pin from a firing pin or thelike to actuate a detonator and thus fire and destroy adjacent mines orother explosive material surrounding the unit. The movable firingelements, which include the detonator and the firing pin, lie in anelongated transverse cylindrical channel at a right angle to andintersecting a similar and larger longitudinal cylindrical channel forthe release and timing elements which include the elastomer timer plug,the plunger and the trigger pin.

The invention described herein may be manufactured, used and licensed byor for the Government for governmental purposes without the payment tous of any royalty thereon.

The present invention relates to time-delay or timing control means forinitiating a function which is particularly adapted to the field ofdemolitions. More particularly the present invention relates totime-delay control means adapted for rendering explosive mine anddemolition devices inactive after a predetermined period of timefollowing a period of effective or tactical use.

It has been found that, under many tactical situations and in manycommercial situations emplaced explosive mine and demolition devicesrequire that they be rendered inactive or destroyed after some timedelay following the desired period of effectiveness or use. There aremany problems involved, if self destruction is considered as a mode.These problems include safety, reliability, cost, method of activation,time to functioning, long-term storage capability and ruggedness towithstand the average commercial and military environments. Theseproblems have been inherent in ordnance devices for a long time and havenever been completely solved.

In the past, in arriving at any solution to these problems a matching orbalancing of one desired parameter against another has been involved.The cost of most devices heretofore produced has also been comparativelyhigh, their activation procedure frequently hazardous, and the time ofoperation considerably variable. These devices have included mechanicalescapements, electrical rundown timers, the dissolving of plasticbarriers, and the transfer of measured amounts of liquid or gas throughorifices. Up to the present, devices of this type have not beensatisfactory mainly because of cost, safety, and arming procedures.

As a requirement for a known low-cost type of mine and as a result ofextensive research into low-cost timing devices compatable therewith, aself destruct or inac- 3,470,819 Patented Oct. 7, 1969 tivation unit hasbeen provided. These mines are made to arm by the evaporation of avolatile solvent which has been found to be effective in principle fortiming purposes.

It is therefore an object of this invention to provide an improvedtime-delay control unit of low-cost construction which may beparticularly adapted for mine destruction and inactivation, in which theprinciple of the evaporation of a volatile solvent is put to effectiveuse with material in suitable form to hold up under long term storageand maintain proper characteristics to assure a high degree ofreliability, and in which a simple and effective release mechanism isprovided to assure adequate functioning of the unit.

It is also an object of this invention to provide an improved andeffective time-delay detonator unit of the type referred to of arelatively small size and low cost adapted to be dispersed in quantityover an area such as a mine field and to be self destructive after apredetermined and adjustable period of time.

In accordance with the invention, materials were sought and found whichresponded to the evaporation process and these were arranged to be usedin a low-cost simple structure of plastic material with metallicinserts. After investigation of various materials it was found thatenlargement or expansion of an elastomer material in a volatile liquidor solvent could be provided with the necessary mechanism to operate ina safe and stable time-delay control unit. The general concept arrivedat was to retain a spring-loaded axially movable firing pin element in acocked position by means of an expanded elastomer element as a result ofabsorbing the volatile solvent to substantially saturation. Uponexposure to the air, the elastomer element gradually loses the solventby evaporation and reduces in size or contracts back to normal,permitting the firing pin to be released to strike a fixed firingelement, such as a detonator or an electrical contact, to initiate afunction such as an explosion process which fires a mine or otherexplosive element with which the device may be associated.

Important features of the present invention are inherent in theselection and use of an elastomer material, and such materials are foundto be silicon rubber compounds or the buna type or styrene type. Thesematerials must be selected to be compatible with the solvents used suchas alcohols of the low molecular type. Among these are methanol,ethanol, propanol or chlorinated hydrocarbons such as the chloroforms,carbon tetrachloride, ethylene chloride and Dupont Freons.

In a preferred form of the invention, a main housing or casing isprovided by two flat plastic cover plates which are held together bymetallic rivets and enclose two cylindrical channels extending at aright angle to each other and intersecting. One channel, which may betermed the main or longitudinal channel, encloses the release and timingelements of the unit, While the other channel, which may be termed thetransverse channel, encloses the firing elements of the unit. In generalthe firing elements include a spring-pressed firing pin movable axiallyalong the transverse channel and a detonator positioned to receive theblow of the firing pin when released.

The firing pin is released by a release or trigger pin which extendsthrough it and is carried on the end or attached to a spring-pressedmovable piston or plunger in the longitudinal channel. The plunger bearsagainst one end of an elongated timer element comprising a body or plugof elastomer material which fills a cylinder or chamber, also comprisingpart of the longitudinal channel for the timing elements, and throughwhich a guide rod for the piston or plunger extends.

The elastomer timer element is expanded to fill the chamber and holdsthe piston or plunger in a position to retain the firing pin retracted.The chamber or cylinder is ventilated so that the volatile solvent maybe evaporated slowly and thus causing the timer element body or plug toshrink or contract, which permits the plunger or piston to follow andmove to withdraw the release or trigger pin from the firing pin. Thisoccurs after a certain period of time and thus actuates the detinatorand fires the unit and the mine or mines or other explosive devicesaround it for destruction or inactivation after a time delay.

The invention will further be understood from the following descriptionwhen considered with reference to the accompanying drawings, and itsscope is pointed out In the appended claims.

In the drawings,

FIG. 1 is a top or plan view of a time-delay detonating unit embodyingthe invention,

FIG. 2 is a view in elevation, and partly in section of the unit of FIG.1, taken on the section lines 2-2 to show further details thereof inaccordance with the invention,

FIG. 3 is a view in elevation, and partly in section of a form of theinvention which is a modification of the unit shown in FIGS. 1 and 2,and

FIG. 4 is a fragmentary view, in elevation, of a portion of the unit ofFIG. 3 showing a detailed modification thereof in accordance with theinvention.

Referring to the drawings, wherein like elements, throughout the variousfigures are indicated by like reference characters, and referringparticularly to FIGS. 1 and 2, right and left cover plates 5 and 6,respectively, of suitable plastic or like material are joined togetherto form a main housing or casing 7. The cover plates are held togetherby a number of rivets or like fasteners 8 and are complementary incharacter to provide the overall housing or casing for the unit as abovereferred to.

The two plates are relatively flat as shown more clearly in FIG. 1, andare enlarged at the rear end, or the left end as viewed in the drawing,to form a cylindrical screw housing 9 which is internally threaded toreceive a manual timing adjustment screw 10. This may be unscrewed fromthe position shown in FIG. 2 and set to any desired position ofwithdrawal. It is held in place by a spring-pressed detent rod 12 whichis substantially -shaped and on an inner end, is engaged by a detentspring 13 to hold the rod 12 in any one of a series of angularly spacedlongitudinally extending peripheral grooves or notches, one of which isshown at 14. An end cap 15 is provided as a cover for the rear end ofthe screw 10 and covers the notch in which the spring 13 is located, asshown more clearly in FIG. 2.

The timing adjustment screw 10 is one of a series of release and timingelements which extend end-to-end as a group forward through the housing7 longitudinally. These include an elastomer timer element 18 in theform of an elongated round body or plug which fills a ventilatedcylinder or chamber 19 which is in axial prolongation of the threadedopening for the screw 10. The timer element or plug 18 bears at its rearend against a backing washer 20 which, in turn, seats against theforward end of the adjustment screw 10 and is rigidly held therebyagainst rearward movement in any position of adjustment. The cylinder 19is ventilated through ventilating openings 21 which are indicated moreclearly in FIG. 1.

In the cylinder or chamber 19 and pressing against the forward end ofthe timer element or plug 18 is a springpressed or spring biased movablepiston or plunger 22 which act as a movable timer-plug follower. Thismay be of steel or other suitable metal and has a central guide rod 23extending therefrom axially through the body or plug 18 and into acentral guide bearing opening 24 in the end of the adjustment screw 10.This bearing opening is of sufiicient depth to permit the rod 23 to movefreely as the piston or plunger 22 moves against and follows the end ofthe body or plug 18 when it contracts in use for timing as will beexplained.

On the forward side or face of the piston or plunger 22, and extendingaxially forward therefrom, is a release or trigger pin 26 which isreduced in diameter to pass through a hole or locking opening in amovable firing pin or firing element 27. The release spring or drivingspring for the plunger or piston 22 is indicated at 28, and is of thecompression type adapted to drive the piston or plunger 22 rearwardly orto the left as viewed in the drawing.

From the foregoing description it will be seen that the release andtiming elements, above described, are arranged in end-to-end relationcoaxially in a longitudinally extending channel through the casing whichmay be indicated generally at 29. Intersecting this channel at a rightangle thereto and extending transversely across the casing between thecover plates is a second channel 33 which is adapted generally to fitthe firing element or firing pin 27 and to hold it in position to guideit. In rear of the firing element or firing pin 27 is a driving spring34 which seats on a spring base or plug 35 inserted into the channel andpinned thereto as indicated at 36. The channel 33 extends through thecasing from one side to the other as indicated and at the opposite endcontains a primer or detonator 37 which is mounted in a holder 38 alsoinserted into the channel and pinned thereto as indicated at 39. Aboutthe detonator 37 the channel 33 is constricted to provide a seat so thatthe detonator cannot enter the channel beyond the position shown in thefigure and is held in a position to be struck by the moving firing pinor firing element 27 upon release by the trigger pin 26'.

The unit is assembled initially with the timer plug 18 in a contractedcondition, and with the release pin 26, the plunger 22 and the releasespring 28 in place. Also the release pin 26 is inserted into the firingpin 27 which is Withdrawn, against the force of the driving spring 34,to the retracted position shown in FIG. 2.

The timing adjustment screw 10 is set back to the desired withdrawnposition to permit the full expansion of the timer plug 18 to take placeas may be desired for any length of operational time, that is, toenlarge the chamber 19 to the desired size or length for the expansionand initial positioning of the plug 18. The unit is then immersed for anumber of hours, such as 20 to 24 for example, in a volatile. solventwhich is readily adapted to be absorbed by and evaporated from the timerplug 18. This plug may be an elastomer such as a silicon rubber compoundor the buna or styrene type. The solvent used may be an alcohol of thelow molecular type such as methanol, ethanol, propanol or a chlorinatedhydrocarbon such as a chloroform, carbon tetrachloride, ethylenechloride or Dupont Freon.

During the time that the complete unit is immersed in the solvent, thelatter flows through the ventilating openings into the body of the timerplug and causes it to expand to fill the chamber 19 and press againstthe piston or plunger 22 and against the backing disc 20 to the fulllength and extent of the chamber as provided by the adjustment of thescrew 10. The more solvent it absorbs the longer the time for itsevaporation and contraction of the timer plug 18 to the point where itis effective to release the firing pin, as will be explainedhereinafter. Later, when briefly removed from the solvent, the detonatorplug 37 is dropped into the channel 33 to its stop position and thedetonator stop plug 38 is inserted and pinned. The unit is thenreimmersed in the solvent and remains in storage therein until it istime for immediate use in the field. If use is to be not too longdelayed and readiness must be maintained, the safety pin 31 may beremoved before the unit is returned to the solvent solution.

For activation of this unit and placing it in use for timed functioningor detonation, it is merely necessary to remove it from immersion in thesolvent and expose it to the air at the desired location. Thus toinitiate the timing cycle for military use it may be attached to orincorporated within an operative mine and will, in due course after arequired time, fire and destroy the mine and thus set off a chainreaction of destruction if others are close enough for that operation.At any time before firing the unit may be returned to the solvent andimmersed therein to interrupt the operation and restore the timingcycle.

The operation of the devices of FIGS. 1 and 2 is such that, as thevolatile liquid evaporates from the timer plug 18, the material beginsto contract and the longi-@ tudinal contraction permits the plunger orpiston 22 to follow and compress it between the piston and the backingwasher 20 until, by force of the release or driving spring 28, thetrigger or release pin 26 is completely withdrawn from the firing pin orfiring element 27 which is then driven forward under the power of thefiring pin spring 34 to carry out a function such as to strike thedetonator and initiate the explosion of any explosive material or minein its immediate vicinity.

It has been found that the present unit is reliable in operation anddependable and eflicient as a time-delay control unit. This is due inpart to selection and use of the elastomer materials referred to, insuitable form as described, which hold up under long term storage andmaintain proper characteristics to assure this reliability. Furthermorethe simple and effective quick release mechanism provided in thestructure as described which is of low cost, easy to manufacture andassemble and also provides for the further reliability and adequatefunctioning of the unit.

If the time is important, the adjustable time control device provided bythe timer screw is desirable, and also it is desirable that the chamber19 and the body 18 of elastomer material be relatively long or elongatedsince it has been evaluated and found to reduce the effects of tolerancevariations on the time to function. The two parts of the casing 7, thatis, the left and right cover plates 6 and 5, are preferably of theejection molded type. These parts may be made of such plastic materialsas high density polyethylene, polystyrene and the like, with metalsprings, firing pin, plunger, release pin and rivets used to drop intoplace in the molded areas provided therefor as shown in FIGS. 1 and 2.The device may be constructed and used as an expendable item since it isreadily made at relatively low cost.

Referring now to FIG 3, a modification of the unit of FIGS. 1 and 2 isshown which involves a further simplification of the construction andarrangement for the firing and electric detonator. In this unit the leftcasing half 40, of substantially triangular shape, is shown with thelongitudinally extending channel 29 and the transversely extendingchannel 33 intersecting at a right angle to each other as in theprevious embodiment. In the channel 29 is the ventilated cylinder orchamber 19 containing the elongated timer element or plug 18 and withthe piston or plunger 22 pressed against the plug 18 by the drivingspring 28, as in the previous embodiment. Also the piston or plunger 22is provided with the forwardly extending trigger pin through the centerof the release spring 28 and the rearwardly extending guide rod 23. Thisis supported at the rear end by a bearing 42 in the casing and extendsint-o a relief chamber 43 at the end thereof. Thus the chamber 19, inthe present example, is closed at the rear end to provide a fixed timersystem or unit. Also the cylinder or chamber 19 is ventilated by asingle wide vent opening 41, instead of a plurality of smaller openings,as either is satisfactory provided sufficient area i available for thedesired rate of evaporation of the solvent within a predetermined timelimit.

Instead of a firing pin, the forward end of the release or trigger pin26 extends through and holds an electrical contact 44 somewhat in theshape of the firing pin of the previous example. This is provided withthe driving spring 34 which seats against a spring base 45 in thechannel. This, in turn, is supported by a fixed plug 46 pinned to thecasing as in the previous example. Herein the spring base 45 is ofconducting material for electrical circuit connections as will be seenand the plug 46 is of nonconducting or insulating material.

The electrical contact 44 is the moving firing element of the unit andupon release by the trigger pin 26 is adapted to engage the fixed firingelement which is an opposite electrical contact 47 positioned in thechannel 33 and supported by an insulating plug 48.

The contacts 44 and 47 are connected in circuit with an electricaldenotator 49, self contained within the unit and connected with anenergizing battery 50* also contained within the unit, as indicated. Themovable contact 44 is electrically connected through the metal drivingspring 34 with the conducting spring base 45, and the circuitconnections with contacts are further completed through the detonatorand the batery 50' by embedded cuit leads 51 in the unit and connectedwith the base 45 and the contact 47 as shown. The detonator and thebattery may be of the hermetically sealed type. The whole unit isassembled as in the previous embodiment, by riveting the two halves orcover plates of the casing to gether at the points indicated in thefigure by the rivet holes.

The operation of this embodiment is substantially the same as that ofthe previous one except that upon contracting of the elastomer timerplug 18 by evaporation of the solvent over a predetermined period oftime, the piston or plunger 22, moving to the left under action of thedriving spring 28 withdraws the release pin 26 from the contact 44 andthis then moves to strike the contact 47, thereby completing anelectrical circuit from the battery through the contacts and the spring34 to the detonator which then fires and initiates any surroundingexplosive material or nearby mines, for example if the detonator isamplified by the addition of explosives. It will be noted that thecontact 44 may be pinned back in a safe position, while charging, by asafety pin 44A inserted therethrough, as in the previous example for thetrigger pin.

Both embodiments of the invention can be adapted for use with a movingdetonator rather than a moving firing pin as the moving firing element.Thus in FIG. 4 for example, as a modification of the unit shown in FIG.3, the moving contact 44 is replaced by a moving plunger 53 whichengages a primer or detonator body or plug 54. The latter is held inplace until firing by the trigger pin 26 which projects beneath it intothe channel 33. The safety pin 44A is then inserted just below thetrigger pin 26 across the channel 33 and above the firing pin 55 whichreplaces the contact 47. The firing pin is thin and relatively fiat andsupported by a plug 56 in rear thereof in the channel 33.

Thus in the present embodiment, the unit may be assembled with allelements in place except the detonator 54, its follower 53, the spring34, and the upper retaining cap. The unit is held together by the rivetsand assembled as before, and immersed in the volatile solvent for anextended period of time during which the solvent expands the timer plug18 and backs up the piston or plunger 22 driving it to compress thespring 28 and move the release pin 26 into the channel 33 and across itsubstantially in the position shown in FIG. 4. When the unit is removedfrom the solvent the safety pin 44 is then inserted to act as a safetypin during the assembly of the detonator. Subsequently the detonator 54and its follower 53 are dropped into the channel 33, followed by thedetonator spring 34 and the detonator spring plug corresponding to thatat 46 in FIG. 3, and not shown in FIG 4. The plug is pinned in place andthe safety pin 44A is then carefully removed and the unit is returned tothe solvent and again completely immersed therein.

For its use, it merely requires exposure to the air to initiate thearming cycle. This can be interrupted by returning it to the liquid. Inoperation and exposed to the air, the volatile liquid evaporates and thetimer material begins to contract. The release spring 28 pushes againstthe plunger 22 and the release pin or triggering pin 26 is moved towardwithdrawal from under the detonator 54 as the material of the plugcontracts because of the loss of volatile liquid. When the release pin26 clears out of channel, the detonator 54 is immediately driven ontothe firing pin 55 by the driving spring 34 and the plunger or follower53 and may be used to explode any explosive material or elementssurrounding the detonator and the unit.

From the foregoing description it will be seen that a time-delay ortiming control unit in accordance with the invention may be ofsimplified low-cost construction involving a two-part separable casingof plastic material and with longitudinal and transverse cylindricalchannels therein for the release and timing elements and for the firingelements, respectively. In the longitudinal channel a ventilatedcylinder or chamber is provided which is filled with an elongated hollowtimer element or plug or elastomer material with a spring-pressedmovable piston or timer plug follower bearing against it and connectedwith a release or trigger pin for a movable firing element or pin in theother or transverse channel. The movable firing element or pin isassociated with a fixed firing element which may be a detonator or anelectrical contact. The timer element is expanded to fill the chamberand hold the firing pin locked when immersed in a volatile fluid tosaturation. Thus a simple and effective low-cost time-delay detonator isprovided for use in deactivation mines and demolition items in thefield.

We claim:

1. A time-delay control unit for demolition operations and the like,comprising in combination:

a two-part separable casing of molded plastic material comprising twofiat cover plates joined together and forming a longitudinally extendingchannel therethrough and a transversely extending channel therethroughat right angles to each other and intersecting,

an elongated ventilated cylindrical chamber in said longitudinal channelbetween the ends thereof and terminating in a cylindrical threaded screwhousing,

an elongated round plug of elastomer material saturated with a volatilesolvent filling said chamber from end to end,

a spring-pressed plunger engaging one end of said plug within saidchamber,

a timer adjustment screw extending into housing to provide an axiallyadjustable backing for said plug at the opposite end from said plunger,

fixed and movable control elements in said transverse channel, and

a trigger pin engaging the movable control element and connected withsaid plunger to move therewith and release said movable control elementfor closure with said fixed element in response to contraction of saidtimer plug after a predetermined time provided by the evaporation ofsaid solvent therefrom.

2. A time-delay detonator unit for mine destruction comprising incombination:

a two-part separable casing of molded plastic material comprising twofiat cover plates joined together and forming a longitudintal extendingchannel therethrough and a transversely extending channel therethroughat right angles to each other and intersecting,

an elongated ventilated cylindrical chamber in and along saidlongitudinal channel in spaced relation to the ends thereof,

an elongated round timer plug of liquid saturable elastomer materialexpanded by a volatile solvent absorbed therein and filling said chamberfrom end to end,

a spring-pressed follower engaging one end of said plug within thechamber,

fixed and movable firing elements in said transverse channel, and

trigger means engaging the movable firing element and connected withsaid plunger to move therewith and release said firing element to moveinto contact with said fixed firing element in response to contractionof said timer plug after a predetermined delay time provided by theevaporation of said solvent therefrom.

3. A time-delay detonator unit as defined in claim 2, wherein adjustablestop means including a cylindrical screw housing on said casing and anadjustment screw therein at the opposite end of said plug is provided tocontrol the expansion limit of said plug and the delay time tofunctioning.

4. A time-delay detonator unit as defined in claim 2, wherein the fixedand moving firing elements are electrical contacts, and wherein firingcircuit connections are provided therewith in said unit.

5. A timing control unit comprising in combination:

a casing having a longitudinal extending channel therethrough,

a ventilated cylindrical chamber in said channel,

an elongated timer plug of elastomer material confined in said chamberand subject to expansion and contraction movement with the absorptionand evaporation of a volatile solvent,

a spring-pressed plunger engaging one end of said plug as a followerelement therefor in expansion and contraction,

fixed and movable control elements in said casing at one end of saidchannel, and

means engaging the movable control element and connected with saidplunger to release said movable control element in response tocontraction movement of said timer plug.

6. A timing control unit as defined in claim 5, wherein the casing is ofa molded plastic material in the group comprising high-densitypolyethylene and polystyrene, and wherein the elastomer plug is asilicone rubber compound with a solvent in the group of alcohols of thelow molecular type.

7. A timing control unit as defined in claim 6, wherein the siliconerubber compounds of the elastomer plug include one of a group includingthe Buna and styrene types, and wherein the alcohols of the lowmolecular type providing the solvent are in one of two groups includingmethanol, ethanol and propanol in one grou and the chlorinatedhybrocarbons such as carbon tetrachloride in the other group.

8. A timing control unit comprising in combination:

a two-part separable casing of molded plastic material comprising twoflat cover plates joined together and forming a longitudinally extendingchannel therethrough,

an elongated ventilated cylindrical chamber in and along said channelbetween and spaced from the ends thereof,

an elongated round timer plug of elastomer material extending throughsaid chamber and being saturable with a volatile solvent to expand andfill said chamber from end to end,

a spring-pressed plunger engaging one end of said plug within thechamber and movable therewith axially of the chamber in expansion andcontraction as a follower element,

a fixed and a spring-pressed movable control element in said casingaligned in spaced relation for impact engagement upon release of saidmovable element from a cocked position,

a trigger pin engaging the movable control element and connected withsaid plunger to move therewith and release said movable control elementin response to contraction of said timer plug after a predetermined timeprovided by the gradual evaporation of said solvent from said timerplug.

9. A timing control unit as defined in claim 7, wherein the plunger isprovided with a trigger pin extending therefrom axially in one directionas the control element engaging means and with a central guide rodextending axially therefrom in the opposite direction longitudinallythrough said timer plug, and wherein an axially adjustable 9/1962ThWaites et al. 102-82 7/1966 Webb 102-82 10 BENJAMIN A. BORCHELT,Primary Examiner

